Which crusade (1202–1204) ended with the sack of Constantinople instead of reaching the Holy Land?

The story behind the answer

Launched in 1202, this campaign was derailed by debt to Venice, which coerced the crusaders into attacking the Christian city of Zara—earning excommunication. Soon after, Byzantine dynastic intrigue drew them to Constantinople to restore a claimant, Alexios IV. When promises of payment and support collapsed, the crusaders seized and brutally sacked the city in 1204, abandoning the original goal of reaching Jerusalem and establishing the short-lived Latin Empire instead.

The detour had enormous consequences: it deepened the schism between the Latin West and Orthodox East, crippled Byzantine power, and indirectly paved the way for the empire’s final fall in 1453. It also exposed how crusading ideals could be overtaken by political and economic interests, with Venice—under Doge Enrico Dandolo—emerging as a major beneficiary.